Well, sorry, I really thought that would solve your problem. I don’t have any Hue devices so perhaps there is an issue related to that specifically that I’m not aware of.
I have a mixture of pocket sockets, Cree bulbs, and GE on/off switches. My experience with these devices and Google Home so far indicates to me that Google Home doesn’t really care if the device is a in wall switch, pocket socket, or smart bulb. When I ask for all the lights to be turned on, they are, even though some are connected to pocket sockets and some are smart bulbs, and not all of my devices have bulb icons next to them either. When I ask for all the fans to be turned on they are although they are all connected to GE on/off switches. Google Home as far as I can tell isn’t really aware of the nature of the device so even though I have lights on pocket sockets they are treated as lights by Google Home.
Perhaps someone with more experience related to Hue may be able to add to this thread and help you out more. You may be right, this may be a SmartThings issue but again, I don’t think Google Home cares if it’s a switch or a bulb.